<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
  <title>BPicture specifications</title>
  <meta http-equiv="content-type"
 content="text/html; charset=ISO-8859-1">
  <meta name="author" content="Marc Flerackers(mflerackers@androme.be)">
  <meta name="description"
 content="BPicture specifications for OpenBeOS">
</head>
<body>
<span style="font-weight: bold; text-decoration: underline;"></span>Author:
Marc Flerackers<br>
Revision: 1.4<br>
<span style="font-weight: bold; text-decoration: underline;"></span><span
 style="font-weight: bold; text-decoration: underline;"><br>
Picture data</span><br>
<br>
The data of a BPicture is composed of instructions.<br>
<br>
These instructions have a small header, which looks as follows:<br>
<br>
<table cellpadding="2" cellspacing="2" border="1"
 style="text-align: left;">
  <tbody>
    <tr>
      <td>int16</td>
      <td valign="top">id</td>
      <td valign="top">The instruction id</td>
    </tr>
    <tr>
      <td valign="top">int32</td>
      <td valign="top">size</td>
      <td valign="top">The size of the data</td>
    </tr>
  </tbody>
</table>
<br>
After this header the data follows. There are two exceptions:
EnterStateChange and EnterFontState. These are used to enclose state and
font changes. For ExitStateChange and ExitFontState there are no
instructions, this is not needed as we know the size of the instruction
block in the header of the Enter* functions.<br>
<br>
These are the known instructions at the moment:<br>
<br>
<table cellpadding="2" cellspacing="2" border="1"
 style="text-align: left; width: 100%;">
  <tbody>
    <tr>
      <th valign="top">Id<br>
      </th>
      <th valign="top">Name<br>
      </th>
      <th valign="top">Size<br>
      </th>
      <th valign="top">Data<br>
      </th>
    </tr>
    <tr>
      <td valign="top">0x0010<br>
      </td>
      <td valign="top">MovePenBy<br>
      </td>
      <td valign="top">4<br>
      </td>
      <td valign="top">BPoint where<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0100<br>
      </td>
      <td valign="top">StrokeLine<br>
      </td>
      <td valign="top">16<br>
      </td>
      <td valign="top">BPoint start<br>
BPoint end<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0101<br>
      </td>
      <td valign="top">StrokeRect<br>
      </td>
      <td valign="top">16<br>
      </td>
      <td valign="top">BRect rect<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0102<br>
      </td>
      <td valign="top">FillRect<br>
      </td>
      <td valign="top">16<br>
      </td>
      <td valign="top">BRect rect<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0103<br>
      </td>
      <td valign="top">StrokeRoundRect<br>
      </td>
      <td valign="top">24</td>
      <td valign="top">BRect rect<br>
BPoint radii<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0104<br>
      </td>
      <td valign="top">FillRoundRect</td>
      <td valign="top">24<br>
      </td>
      <td valign="top">BRect rect<br>
BPoint radii</td>
    </tr>
    <tr>
      <td valign="top">0x0105<br>
      </td>
      <td valign="top">StrokeBezier<br>
      </td>
      <td valign="top">32<br>
      </td>
      <td valign="top">BPoint[4] control</td>
    </tr>
    <tr>
      <td valign="top">0x0106<br>
      </td>
      <td valign="top">FillBezier<br>
      </td>
      <td valign="top">32<br>
      </td>
      <td valign="top">BPoint[4] control</td>
    </tr>
    <tr>
      <td valign="top">0x010B<br>
      </td>
      <td valign="top">StrokePolygon<br>
      </td>
      <td valign="top">4 + point data size + 1<br>
      </td>
      <td valign="top">int32 numPoints<br>
BPoint *points<br>
bool isClosed<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x010C<br>
      </td>
      <td valign="top">FillPolygon<br>
      </td>
      <td valign="top">4 + point data size </td>
      <td valign="top">int32 numPoints<br>
BPoint *points<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x010D<br>
      </td>
      <td valign="top">StrokeShape<br>
      </td>
      <td valign="top">shape data size<br>
      </td>
      <td valign="top">shape data, see below </td>
    </tr>
    <tr>
      <td valign="top">0x010E </td>
      <td valign="top">FillShape </td>
      <td valign="top">shape data size </td>
      <td valign="top">shape data, see below </td>
    </tr>
    <tr>
      <td valign="top">0x010F<br>
      </td>
      <td valign="top">DrawString<br>
      </td>
      <td valign="top">4 + string data size + 8<br>
      </td>
      <td valign="top">strlen<br>
char *string<br>
float deltax<br>
float deltay<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0110 </td>
      <td valign="top">DrawPixels<br>
      </td>
      <td valign="top">56 + pixel data size<br>
      </td>
      <td valign="top">BRect src<br>
BRect dest<br>
int32 width<br>
int32 height<br>
int32 bytesPerRow<br>
int32 pixelFormat<br>
int32 flags<br>
int32 length of pixel data<br>
pixel data<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0112<br>
      </td>
      <td valign="top">DrawPicture<br>
      </td>
      <td valign="top">12<br>
      </td>
      <td valign="top">BPoint where?<br>
????<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0113</td>
      <td valign="top">StrokeArc<br>
      </td>
      <td valign="top">24<br>
      </td>
      <td valign="top">BPoint center<br>
BPoint radii<br>
float startTheta<br>
float arcTheta<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0114<br>
      </td>
      <td valign="top">FillArc<br>
      </td>
      <td valign="top">24<br>
      </td>
      <td valign="top">BPoint center<br>
BPoint radii<br>
float startTheta<br>
float arcTheta</td>
    </tr>
    <tr>
      <td valign="top">0x0115<br>
      </td>
      <td valign="top">StrokeEllipse<br>
      </td>
      <td valign="top">16<br>
      </td>
      <td valign="top">BRect rect<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0116</td>
      <td valign="top">FillEllipse</td>
      <td valign="top">16<br>
      </td>
      <td valign="top">BRect rect</td>
    </tr>
    <tr>
      <td valign="top">0x0200<br>
      </td>
      <td valign="top">EnterStateChange<br>
      </td>
      <td valign="top">size of state instructions<br>
      </td>
      <td valign="top">state instructions</td>
    </tr>
    <tr>
      <td valign="top">0x0201</td>
      <td valign="top">SetClippingRects</td>
      <td valign="top">16 + size of rects<br>
      </td>
      <td valign="top">clipping_rect bound<br>
clipping_rect *rect</td>
    </tr>
    <tr>
      <td valign="top">0x0202</td>
      <td valign="top">ClipToPicture</td>
      <td valign="top">7 + 8 + 1 </td>
      <td valign="top">zero bytes<br>
BPoint pt<br>
bool clip_to_inverse_picture<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0203<br>
      </td>
      <td valign="top">PushState<br>
      </td>
      <td valign="top">0<br>
      </td>
      <td valign="top"><br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0204</td>
      <td valign="top">PopState</td>
      <td valign="top">0<br>
      </td>
      <td valign="top"><br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0205<br>
      </td>
      <td valign="top">SetClippingRects </td>
      <td valign="top">0 </td>
      <td valign="top">This is a shorter instruction for 0 clipping
rects.<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0300<br>
      </td>
      <td valign="top">SetOrigin<br>
      </td>
      <td valign="top">8<br>
      </td>
      <td valign="top">BPoint pt<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0301<br>
      </td>
      <td valign="top">SetPenLocation<br>
      </td>
      <td valign="top">8<br>
      </td>
      <td valign="top">BPoint pt<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0302<br>
      </td>
      <td valign="top">SetDrawingMode<br>
      </td>
      <td valign="top">2<br>
      </td>
      <td valign="top">drawing_mode mode<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0303</td>
      <td valign="top">SetLineMode<br>
      </td>
      <td valign="top">2 + 2 + 4<br>
      </td>
      <td valign="top">cap_mode capMode<br>
join_mode joinMode<br>
float miterLimit<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0304<br>
      </td>
      <td valign="top">SetPenSize</td>
      <td valign="top">4<br>
      </td>
      <td valign="top">float size<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0305<br>
      </td>
      <td valign="top">SetScale<br>
      </td>
      <td valign="top">4<br>
      </td>
      <td valign="top">float scale</td>
    </tr>
    <tr>
      <td valign="top">0x0306<br>
      </td>
      <td valign="top">SetForeColor<br>
      </td>
      <td valign="top">4<br>
      </td>
      <td valign="top">rgb_color color<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0307<br>
      </td>
      <td valign="top">SetBackColor<br>
      </td>
      <td valign="top">4<br>
      </td>
      <td valign="top">rgb_color color</td>
    </tr>
    <tr>
      <td valign="top">0x0308<br>
      </td>
      <td valign="top">SetStipplePattern<br>
      </td>
      <td valign="top">8<br>
      </td>
      <td valign="top">pattern p<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0309<br>
      </td>
      <td valign="top">EnterFontState<br>
      </td>
      <td valign="top">size of font instructions</td>
      <td valign="top">font instructions</td>
    </tr>
    <tr>
      <td valign="top">0x030A<br>
      </td>
      <td valign="top">SetBlendingMode<br>
      </td>
      <td valign="top">4<br>
      </td>
      <td valign="top">source_alpha alphaSrcMode<br>
alpha_function alphaFncMode<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0380<br>
      </td>
      <td valign="top">SetFontFamily<br>
      </td>
      <td valign="top">4 + string data size</td>
      <td valign="top">strlen<br>
char *family<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0381<br>
      </td>
      <td valign="top">SetFontStyle<br>
      </td>
      <td valign="top">4 + string data size</td>
      <td valign="top">strlen<br>
char style</td>
    </tr>
    <tr>
      <td valign="top">0x0382<br>
      </td>
      <td valign="top">SetFontSpacing<br>
      </td>
      <td valign="top">4<br>
      </td>
      <td valign="top">int32 spacing<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0383<br>
      </td>
      <td valign="top">SetFontEncoding<br>
      </td>
      <td valign="top">4<br>
      </td>
      <td valign="top">int32 encoding<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0384<br>
      </td>
      <td valign="top">SetFontFlags<br>
      </td>
      <td valign="top">4<br>
      </td>
      <td valign="top">int32 flags<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0385<br>
      </td>
      <td valign="top">SetFontSize<br>
      </td>
      <td valign="top">4<br>
      </td>
      <td valign="top">float size<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0386<br>
      </td>
      <td valign="top">SetFontRotate<br>
      </td>
      <td valign="top">4<br>
      </td>
      <td valign="top">float rotation<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0387<br>
      </td>
      <td valign="top">SetFontShear<br>
      </td>
      <td valign="top">4<br>
      </td>
      <td valign="top">float shear(is 0 instead of 90?)<br>
      </td>
    </tr>
    <tr>
      <td valign="top">0x0389<br>
      </td>
      <td valign="top">SetFontFace<br>
      </td>
      <td valign="top">4<br>
      </td>
      <td valign="top">int32 flags<br>
      </td>
    </tr>
  </tbody>
</table>
<br>
There are a few undocumented instructions:<br>
<br>
<table cellpadding="2" cellspacing="2" border="1"
 style="text-align: left;" width="100%">
  <tbody>
    <tr>
      <td valign="top">0x0388<br>
      </td>
      <td valign="top">SetFontBPP </td>
      <td valign="top">4<br>
      </td>
      <td valign="top"> int32 bpp (default 8)<br>
      </td>
    </tr>
  </tbody>
</table>
<br>
Not all instructions where checked yet. The SetClippingRects has still
to be documented.<br>
<br>
DrawPicture and ClipToPicture have an index to the sub-picture. In
flattened data, these sub-pictures are stored in front of the main
picture data, when archived to a BMessage, the sub-pictures are
contained in a field called "piclib".<br>
<br>
<span style="font-weight: bold; text-decoration: underline;">Shape data</span><br>
<br>
The shape data contained in a BPicture is stored as follows:<br>
<br>
<table cellpadding="2" cellspacing="2" border="1"
 style="text-align: left;" width="100%">
  <tbody>
    <tr>
      <td valign="top">int32<br>
      </td>
      <td valign="top">instruction count<br>
      </td>
    </tr>
    <tr>
      <td valign="top" rowspan="1" colspan="1">uint32 *instructions<br>
      </td>
      <td valign="top" rowspan="1" colspan="1">Each instruction looks
like:<br>
First byte is the instruction id<br>
The next three bytes is the amount of points used*<br>
      </td>
    </tr>
    <tr>
    </tr>
    <tr>
      <td valign="top">int32<br>
      </td>
      <td valign="top">point count<br>
      </td>
    </tr>
    <tr>
      <td valign="top">BPoint *points </td>
      <td valign="top">points<br>
      </td>
    </tr>
  </tbody>
</table>
<br>
<table cellpadding="2" cellspacing="2" border="1"
 style="text-align: left; width: 100%;">
  <tbody>
    <tr>
      <th valign="top">Id<br>
      </th>
      <th valign="top">Name<br>
      </th>
      <th valign="top">Points*<br>
      </th>
      <th valign="top">Notes<br>
      </th>
    </tr>
    <tr>
      <td valign="top">0x80</td>
      <td valign="top">MoveTo</td>
      <td valign="top"><br>
      </td>
      <td valign="top">
      <ul>
        <li>A "MoveTo" instruction doesn't stand alone, but is OR-ed
with a "LineTo" or "BezierTo" instruction<br>
        </li>
      </ul>
      </td>
    </tr>
    <tr>
      <td valign="top">0x10 </td>
      <td valign="top">LineTo</td>
      <td valign="top">point count in instruction<br>
      </td>
      <td valign="top">
      <ul>
        <li>One "LineTo" instruction draws "count" lines</li>
      </ul>
      </td>
    </tr>
    <tr>
      <td valign="top">0x90 </td>
      <td valign="top">MoveTo LineTo</td>
      <td valign="top">point count in instruction + 1</td>
      <td valign="top">
      <ul>
        <li>There is one extra point for the "MoveTo", which is not
counted in the instruction.<br>
        </li>
      </ul>
      </td>
    </tr>
    <tr>
      <td valign="top">0x20 </td>
      <td valign="top">BezierTo</td>
      <td valign="top">point count in instruction</td>
      <td valign="top">
      <ul>
        <li>One "BezierTo" instruction draws "count" lines</li>
      </ul>
      </td>
    </tr>
    <tr>
      <td valign="top">0xA0 </td>
      <td valign="top">MoveTo&nbsp;BezierTo</td>
      <td valign="top">point count in instruction + 1</td>
      <td valign="top">
      <ul>
        <li>There is one extra point for the "MoveTo", which is not
counted in the instruction.<br>
        </li>
      </ul>
      </td>
    </tr>
    <tr>
      <td valign="top">0x40 </td>
      <td valign="top">Close</td>
      <td valign="top">0 </td>
      <td valign="top">
      <ul>
        <li>"Close" can only follow a "LineTo" or "BezierTo" instruction</li>
        <li>If an instruction follows "Close", the new instruction is
OR-ed with "Close" and replaces it instruction</li>
        <li>A&nbsp;shape never starts with "Close"</li>
      </ul>
      </td>
    </tr>
  </tbody>
</table>
<br>
</body>
</html>
